1、Wireless and battery-free doorbell Outdoor waterproof IP 65 Snow Rain Humidity 2、Why choose a battery-free system?It is well known that batteries do not like humidity, negative temperatures and high heat at all.Rest assured, totally suitable for outdoor use, the battery-free wireless doorbell has absolutely no fear of extreme weather conditions. 3、Guaranteed operation every time!We use a state-of-the-art self-feeding mechanism that is reliable, robust and efficient.also, the extended antenna gives you an excellent range that can pass through walls and slabs without any problems. 4、No need to have a stock and battery at home, save money with your battery-free chime kit.In addition, by avoiding battery changes, you are making an ecological gesture by avoiding the long and complicated recycling of batteries. 5、No complicated programming or other hazardous manipulations.Choose the location of your doorbell, plug the chime into an electrical outlet and that's it.Then you can choose the ringtone volume level and melody that suits you.